#!/usr/bin/env python3
# -*- coding: utf-8 -*-
# the multiprocess pool

from multiprocessing import Pool
import time
import os
import random

def long_time_task(name):
    print('run task %s (%s)...' % (name, os.getpid()))
    start = time.time()

    time.sleep(random.random() * 3)

    end = time.time()

    print('task %s runs %0.2f secounds' %(name, (end - start)))

if __name__ == '__main__':

    print('parent process %s.' % os.getpid())
    p = Pool(4)
    for i in range(6):
        p.apply_async(long_time_task, args=(i, ))
    print('waiting for all subprocesses done...')
    p.close()
    p.join()
    print('all subprocesses done...')

